How can Oracle change the character set?

There are several methods for changing the character set of an Oracle database.

1. Modify using the Database Configuration Assistant (DBCA): During the installation of an Oracle database, you can choose the desired character set. If you need to change the character set, you can run DBCA and select to modify the character set of an existing database instance.
2. You can modify the character set of a database using the ALTER DATABASE statement. Here is an example.
3. Change the character set of the database to new_character_set.
4. Among them, new_character_set is the name of the new character set.
5. Modify character set by setting the NLS_LANG environment variable.示例如下：
6. Set the NLS_LANG environment variable to AMERICAN_AMERICA.AL32UTF8.
7. AMERICAN_AMERICA.AL32UTF8 is a new character set.

It is important to note that changing the character set may result in data loss or corruption, so it is recommended to backup the database before making any modifications and conducting thorough testing and validation. Additionally, changing the character set typically requires recreating the database instance.